


Blood Pact

by AmkiTakk



Category: Durarara!!
Genre: Alley Sex, Blood Drinking, Creampie, M/M, Trans Orihara Izaya, Vaginal Sex, Vampires
Language: English
Status: Completed
Published: 2020-12-04
Updated: 2020-12-04
Packaged: 2021-03-10 00:46:13
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 4,250
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/27885469
Author URL: https://archiveofourown.org/users/AmkiTakk/pseuds/AmkiTakk
Summary: In which Shizuo loses control after one of their infamous chases and bites Izaya, who ends up liking that a bit too much.__Written for Shizaya Week Day 3, prompt chosen was "Vampire AU".
Relationships: Heiwajima Shizuo/Orihara Izaya
Comments: 2
Kudos: 111
Collections: Shizaya Week 2020





	Blood Pact

**Author's Note:**

> Hello I come with more smut (featuring more trans Izaya because I am unstoppable).  
> It's slightly longer than I planned whoops.
> 
> (Not betaed and barely even proof-read because it's midnight and I'm too lazy to check it over lol)

Things had happened as they usually did. They hadn't done anything different from what they usually did. They had engaged in their usual dance of stinging words and flying public property, then, when he had played enough for that day, Izaya took off into the maze-like alleys of Ikebukuro to lose the predator that was chasing him.

So how did it come to this?

Izaya had ran and ran, yet he couldn't lose the damn beast, who seemed not only more pissed than usual, but also was much faster. Had he gone too far in his taunting and now the blonde was truly trying to kill him instead of simply chasing him off?

Shizuo was having no problem keeping up with Izaya's own impressive speed and parkour moves, hell, he was actually gaining on him the longer they kept going.

It was only a matter of time before the exhaustion would get to either of them and, it turned out, Izaya was the one to fall from it first.

Literally.

Thanks to the unfortunate combination of his exhaustion with the currently pouring rain, Izaya slipped and found himself sprawled on his stomach over the dirty ground of an empty alley.

Without hesitation, and as if possessed, Shizuo leaped and jumped over Izaya, effectively pinning him to the ground by grabbing his hands and using his own legs to trap Izaya's.

Izaya barely had the time to realize what was going on before he felt a sharp pain in his neck—

Then overwhelming pleasure.

Distantly, he was vaguely aware of the beast's mouth on his neck. His mind was foggy, he couldn't bring himself to move, nor to think of anything. He just laid there as he gradually felt all his strength leaving his body.

His limbs were trembling all over and he could feel a quite familiar  _ something _ build up in his lower body with each drop of blood that left his body and went into Shizuo's own.

Eventually, it was all too much, his whole body tensed up and his vision, already blurry, went white. He let out an almost pained whine as he felt his orgasm come in waves until, finally, Shizuo released Izaya's neck and stood up from his place over him.

He observed his handiwork in silence, leaving Izaya there on the ground, trembling and breathing heavily.

"...Shit."

...

"Well, I was expecting it to happen eventually, it  _ has _ been a month and I'm sure you haven't been feeding properly again. I'll be honest though, I'm more surprised that it's  _ him _ , of all people." Shinra said, looking up and down Shizuo and the dazed informant he had thrown over his shoulder.

Shizuo looked away guiltily. He had let his instincts take over again and ended up hurting someone in the process. Even if that person was the flea, he still didn't feel too good about losing control once more.

"Yeah. Sorry about that..." Shizuo went in and dumped Izaya and Shinra's couch none-too-gently. "Anyway, can you check him out?"

Shinra quirked an eyebrow. "I certainly can, but you know, you're always going on about how you'd kill him. Isn't this the perfect opportunity?" He asked with an amused smile while he went to check Izaya's vitals. He was pale (no surprise there, considering he had probably been drained of a considerable amount of blood), but his pulse was normal, if a little faster than usual when compared to Shizuo's other 'snacks'. Interesting.

"I'm not like him. I'm not gonna kick him when he's down." Shizuo huffed.

"How chivalrous!" Shinra teased, then stood up, leaving Izaya to rest on his couch. "Well, the good news is that he's not in immediate danger. Rest and appropriate hydration will be the only treatment he needs."

"...You make it sound like there's also bad news." Shizuo frowned.

"Ah nothing like that! It's more of an interesting detail, really. Say, was his reaction any different than usual?"

"Uh, I don't think so? He was as annoying as usual."

"Ah, no, I meant compared to the other people you drank from."

At that, Shizuo flinched, guilt present in his eyes. He looked at the now-asleep Izaya then back to Shinra.

"I hurt him. Usually they don't feel a thing but towards the end he kinda...cried?"

"How so? Did he scream or something?"

"No, but he made some kind of, uh, whimper, I guess? It sounded like he was in pain..." Shizuo scratched his hair absent-mindedly.

Shinra hummed. "And you're sure he was in pain?"

"Well why else would that louse make this kinda sound?" Shizuo was getting annoyed with Shinra's questions. He was already pissed enough after losing control, he certainly didn't need the doctor to be prodding him like that. "What's it to you anyway? You think he managed to fake it or some shit even though I put him in  _ that _ state? Don't be ridiculous."

Shinra laughed and brought his hands up to appease his friend. "No way no way, that thing you do puts people in a trance, it'd be pretty much impossible for anyone to resist. No, I mean he could have made that noise for another reason than pain."

"Like what?"

"Pleasure. The carnal kind—"

And then Shinra's coffee table went flying right through his window.

...

When Izaya's eyes opened, he was met with a familiar ceiling.

"So sleeping beauty awakes!" An annoying voice commented.

Ah, Shinra. Of course. He sighed.

"It would appear so. Although I have no memory of ever falling asleep at your place. Did you drug me again, Shinra?" Izaya gave him a smirk but made no move to get up from Shinra's couch. For some reason, his whole body felt incredibly relaxed, as if he had gotten some really good workout.

"Oh come on, I only did that once, and it was for science!" Shinra spoke as if Izaya had accused him of stealing from the cookie jar. His smile was completely unrepentant, though.

"For science or not, drugging your friends without their consent or knowledge is still inappropriate, Shinra." Not like Izaya could speak much about what was appropriate within a friendship or not, considering his only friend was  _ Shinra _ .

Shinra laughed and gave him a glass of water. Well, he did feel pretty thirsty, now that he thought about it.

"So, what do you remember?" The doctor asked him once he had finished the whole glass.

"Why, I took Shizu-chan out for a run and we played for a bit. Business as usual!" He smirked.

"Right, anything else? Do you know how you ended up here?"

"Hm, not really. Did Shizu-chan knock me out, perhaps?" He wondered aloud. His head didn't hurt though, and neither did the rest of his body. What actually happened? He wasn't feeling the after-effects of some drugs either, his mind perfectly lucid.

"Well, I checked you over but you didn't seem to have any injuries, so guess he didn't!" Shinra said brightly, and Izaya looked at him suspiciously.

"You know what happened, don't you." He stated flatly.

"Who knows!" He laughed.

"...Guess a certain courier is going to have a lot of work this month. Seems like someone will have to spend some time alone, huh?"

"Shizuo did it."  _ Too easy. _

"Right, and what did he do, exactly? He doesn't seem to be the type to drug people. He's more of a brute force kind of monster."

Shinra gave him a knowing grin.

"Well, why don't you ask the man himself, then?" And just as Shinra was done saying that, the front door opened.

"Hey Shinra, how is—"

Silence.

Izaya stared at the newcomer, a certain familiar blonde man with violent tendencies. Shizuo stared at him blankly.

Then promptly turned around and left the apartment.

...

Fuck. Shit. Fuck fuck fuck fuck fuck fuck fuck fuck.

That flea sure woke up quickly! Usually they'd sleep for at least one or two days, but here that louse was, awake and full of energy!

Shizuo was not ready to see him awake so soon. He wasn't prepared mentally, especially not after what Shinra had said the night before.

Pleasure? The carnal kind? What kind of perverted bullshit was that! That sort of thing only happened in corny vampire movies, but this was reality! Yeah, his...kind did have some sort of hypnosis powers that would make their...victims numb, it was easier to eat when your source of food wasn't writhing in pain. It also temporarily gave the victim fast healing abilities, so there was no trace left once they woke up.

But however that power worked, it didn't give any sort of pleasure!

Shinra was a pervert.

And yet Shizuo couldn't stop thinking about what he said, and that whimper.

"Heh, I don't recall ever being the one to chase you."

Oh no. Shizuo stiffened.

"What do you want."

"Touchy, aren't we? I just want to know..." Izaya removed the hand he had in his pocket and pointed his knife towards Shizuo with a threatening smile. "What did you do to me? And before you claim innocence, don't bother, Shinra told me."

"That damn blabbermouth..." He growled.

"You should know better than to trust Shinra to keep secrets. Now, tell me exactly what you did to me and maybe I won't pin another crime on you." Izaya gave him a bright smile that gave him chills.

Shizuo took a wary step back.

"I knocked you out with a trashcan so I brought you to Shinra.

Something sharp whizzed right past Shizuo's ear.

"You're an awful liar, Shizu-chan. Why would you bother keeping it a secret anyway? What heinous things did you do to me while I was out?"

_ I hypnotized you, drank your blood, and Shinra suspects it made you feel good. _

Yeah, no way he was going to say that.

So he ran. Again.

"Hey, don't run away, that's my thing!"

And then began something Ikebukuro would never forget : Orihara Izaya chased Heiwajima Shizuo through the streets in some reversal of their usual game of cat and mouse.

Except Izaya was an expert at running away, unlike Shizu-chan, who quickly found himself in an alley with no possible exit. He was cornered.

"You can't run anymore, Shizu-chan~" Izaya sing-songed, twirling yet another knife. Where did this guy hide all those anyway?

Izaya kept coming closer until Shizuo had flattened himself against the wall. He could destroy it and run, but where would that bring him? More debts and a pissed-off Izaya would wouldn't give up chasing after him until he had gotten answers anyway.

Better come clean, but...

Shizuo gulped, the truth sounded kinda bad. No, really bad. And it would prove to Izaya that he was, indeed, a monster.

But Izaya didn't give up easily, if his constant tormenting of Shizuo was any indication.

Well, here goes...

"I drank you."

"Pardon?"

Shizuo gulped. Okay that didn't sound good.

"I, huh. I drank your blood."

Izaya stared at him blankly.

...Should he laugh? But Shizuo's current expression...

"...You're serious."

"...Yeah."

"Why. Is that some kind of beastly thing? Or some kind of fetish?"

Argh, why did it always come down to sex stuff! It wasn't like that!

"NO! I-I mean, no, that's not...like that. I just..."

"Shizu-chan, I know you only have one functioning brain cell but I'm going to need you to use your words smartly, or you will be in big, big trouble." He threatened. Shizuo gulped.

"I can explain! It's none of what you're thinking! Well, mostly. It's nothing...sexual."

"Right. It better not be."

"The thing is...I'm...kind of like a vampire? Not exactly since I don't fear the sun or garlic or none of that fiction nonsense. I just...need blood on top of normal food?" He tried to explain, and immediately got a knife right at his neck.

"You want me to believe that?"

"...I honestly don't expect you to. But that's the truth." Shizuo closed his eyes, then opened them back up.

Izaya froze.

The earnest eyes staring right at him were now a bright yellow. A familiar bright yellow that brought back memories.

Specifically, memories of last night.

...

After their altercation, both men had gone their own way and hadn't seen each other since.

For his part, Shizuo had avoided Izaya like the plague. Thankfully, Izaya hadn't seemed like he'd use this specific information as blackmail, possibly because it was so hard to believe in the first place.

Izaya, meanwhile, had pretty much harassed Shinra for more information. Now that the secret was out, he was a bit too happy to go on a rant about Shizuo's physiology.

Apparently, Shizuo had a tendency to not feed properly. He'd avoid drinking blood for as long as he could before ultimately losing control of his hunger and attacking random people in the night. The venom from his bite would typically cause numbness and put the victim in a trance-like state, making sure they would neither fight back nor have any memory of having ever been bitten at all. The venom would also highly stimulate the body's regenerative abilities, so there would be no trace of the bite.

Well, it certainly stimulated  _ something _ in Izaya. Not just his healing though.

Shinra knew so much, Izaya suddenly understood why Shizuo got so annoyed about him mentioning dissections. The illegal doctor had probably performed quite a few on him before Shizuo had had enough of that and started threatening him each time he would ask.

The one detail that had gotten Izaya's attention, however, was the fact that victims would typically sleep for two or three days depending on the amount of blood taken, their pulse having greatly been slowed thanks to the venom. Because Izaya knew for a fact : he had barely even slept a day. Actually, he had simply slept through the night like any normal person would have (which, admittedly, was much longer than Izaya was used to) and woken up fully rested come morning.

Not only that, but according to Shinra, his pulse, unlike usual, had actually been slightly  _ faster _ than normal.

That, as well as the sheer pleasure he had remembered feeling had piqued his interest.

What had caused that difference? Was it because they were of the same blood type? Did the venom interact weirdly with the adrenaline that was coursing through Izaya's veins thanks to the chase? Was it some strange supernatural thing based off of his emotions, meaning he perhaps had some secret lust for his sworn enemy?

Izaya couldn't help but be curious. No, actually, he was absolutely  _ fascinated _ .

You see, although Izaya would never admit it to anyone, Shizuo had always interested him; from the rumors he heard before meeting him to his rejection at first sight, Izaya had found him so fascinating to observe. He was so unpredictable in the best ways! Not in the ironically predictable way humans were, but in his own, truly unpredictable way. Shizuo was a being of pure instinct and emotion, which made it hard for Izaya to predict his actions, yet that was exactly what was so exciting about messing with him.

And now, he learned that Shizuo was quite literally a blood-sucking monster? The irony felt absolutely  _ fantastic _ .

So, of course, Izaya decided to play with him again.

For observation purposes, of course.

...

Shizuo felt like he was losing his mind. He kept smelling the flea everywhere he went, yet would never find him. He felt eyes on him in all places except his own home, and despite all the clear signs of Izaya being there...he never saw him.

The flea was playing another of his mind games with him, and for once Shizuo was actually wary, instead of annoyed.

No good would come of that when Izaya had such critical information on him.

To top it all, Shizuo was once again reaching his limit, he had to drink soon or lose control once more, and if he did? He knew Izaya would take full advantage of it.

Last time had been a disaster, since the person he had fed from was the worst possible one, so he decided to ask Shinra just this once. Hopefully he had some blood bags to spare, otherwise, if push comes to shove...he'll have to drink from the doctor himself at the price of playing guinea pig again.

He didn't really want to, but it's not like he had much of a choice. Shinra was the only one who knew outside his family, and he didn't want to wait too long again in case Izaya caught him in the act.

"Heya Shizu-chan! Looking for a late-night snack?"

Speaking of the devil.

"Fuck off."

"Why so much hostility? Just making small talk~" Suddenly, Izaya was right in Shizuo's face, grinning. "Going to hunt for some poor, unsuspecting victim to brainwash into giving you their life source? Or perhaps did you learn your lesson and decide to find someone who'd willingly let you leech off them? Silly Shizu-chan, you know the only other person both aware of your condition and able to give you blood is Shinra. Are you that desperate?"

"What do you know?" Shizuo growled, clenching his fists in growing anger. "It's not like I want to! But if I don't then I'll...I'll lose control again." His tone significantly lowered at the end, his fists unclenching.

Izaya blinked at the resigned expression on Shizuo's face. Well that was no fun. He wanted anger and had almost gotten it!

But this could be interesting too, Izaya was nothing if not adaptable after all. He could play with this.

"Aww, no need to make such a face, I'm actually here with a proposition for you!"

"A...proposition." Shizuo stared at Izaya suspiciously.

"Why yes, I, yours truly," He said, dramatically putting his hand on his chest in some sort of grand gesture, "Will help you with your little condition!"

"Hell no. I don't trust you."

"I'd be surprised if you did, but hear me out— "

"No."

"Come on— "

"No."

"Shizu-chan"

"No."

"Bit me."

"N— Excuse me??"

"Come on, it's easy, just chase me into some dark alley and take your fill, easy no? And people will keep away because of our respective reputations, so you won't get caught!" Izaya had a bright, excited smile. Shizuo decided he hated it even more than his usual shit-eating grin.

"You've probably planned some shady shit, like usual. I'm going, now fuck off." Shizuo started to walk around Izaya, but the informant just stepped right in his path, blocking the way with each sidestep he took.

Shizuo's patience was starting to run thin, and the thirst certainly didn't help.

"Won't you believe in that one percent already?"

"No. Get out of my way."

"Nope. At least consider it!"

"Hell no. Go. Away."

"Come on~"

Veins were starting to show on Shizuo's face.

"I'm gonna beat your ass."

"Just a little bite, is that too much to ask for?"

"Izaya"

"Shizu-chan~"

So that pest wanted a chase?

"Run."

Well, he was gonna get one.

...

They ran, and ran. The night dwellers of Ikebukuro, too, were used to that spectacle and simply avoided the trail of destruction to avoid getting caught in it.

Eventually, they had ended up in a dead end in some alley away from the most populated areas. Shizuo grinned manically at having finally cornered his prey.

Then he saw Izaya's expression and realized.

He had been had.

But honestly, at this point he was too pissed to care, so he went in for the kill. He pushed the grinning Izaya right against the wall, creating cracks in it from the strength of the hit.

He brought his face close to Izaya"s with a snarl.

"I'm not making any deal with you, just so you know."

Izaya smiled, unperturbed.

Then Shizuo went for his neck and  _ bit _ .

Izaya's blood was absolutely delicious. Almost as delicious as the gasp that escaped he throat.

Which had sounded oddly...erotic.

Izaya's hand had immediately flown to his mouth to try and muffle the sound, but it was too late.

Shizuo had heard. And he wanted to hear it again, he realized.

So hit bit down harder and was rewarded with a trembling, muffled moan.

So Shinra had been right after all. Maybe Izaya was a masochist, and that had somehow overwritten the usual numbness. Well, Shizuo didn't really care and drank on.

Against him, Izaya was trembling. Now Shizuo knew why he had been so insistent, that pervert. Man, was that guy fucked up.

Meanwhile, Izaya was in pure ecstasy. He had wanted to try being bitten again to see if things would feel different, and while the pleasure he felt was the same as before, his mind felt different. Clear.

Shizuo was slowly sucking on his neck, letting blood flow from the puncture wounds right into his throat.

They stayed like that for a few minutes, until Shizuo finally had his fill and removed his mouth from Izaya's neck. The wound quickly closed from the venom's effect.

Izaya had kept quiet the whole time, except for the stray moan here and there, but whined at the sudden loss.

"...Wait, keep going." He asked in a low, trembling voice. Shizuo took a good look at him.

He was still trembling all over, cheeks flushed and breathing heavy. He looked like he was on the very edge of coming all over himself.

It was quite the arousing sight, if Shizuo was honest with himself.

He didn't hesitate and kissed the informant right there, swallowing every gasp. Izaya sounded like he didn't know whether he wanted to protest or not, but eventually relented. He grabbed his sleeve with one hand and slid the other at the back of his head to both caress the mass of hair there as well as deepen the kiss.

What happened next was a blur. They didn't even bother taking most of their clothes off, simply opening their pants and lowering their underwear. Shizuo had briefly paused when he had gone to grab the informant's groin, only for his hand to find something much smaller, but he just shrugged and went along with it, instead moving his fingers to play with the very wet opening he found there.

They kept kissing, and he kept fingering Izaya, earning himself some more delicious moans that he gladly swallowed with more kissing.

Eventually he removed his fingers and Izaya growled, about to protest until he felt something much bigger prod at his entrance.

Shizuo entered him slowly, pressing them both further into the wall.

When he finally bottomed out, they both sighed in relief, Izaya spreading his legs as much as he could considering their current position and the clothes still partially in the way.

"Move."

Well, he certainly didn't need to be told twice.

He slowly removed himself until only the tip was still inside Izaya...then pushed right in, making him squeal. He repeated that movement, enjoying the feeling of Izaya's wet walls squeezing him hard whenever he bottomed out.

He kept a steady rhythm, slowly back out, quickly go back in, again, and again, and again. In the dark alley, the only sounds one could hear were that of obscene, wet squelching and heavy breathing.

If anyone found them, they'd both be in big, big trouble. Of course, Izaya had made sure to pick a specific spot that he knew nobody would frequent at this time of day, but the risk of a random passerby finding them was still there. And it made it all the more exciting to Izaya.

It was like one of his fantasies becoming reality : being fucked like a beast by Ikebukuro's Strongest in some dirty alley that just about anyone could walk into. To say Izaya was having the time of his life was quite the understatement.

He could feel heat in his lower body as well as his body tensing up. He was close, and if Shizuo's more erratic pace and growls were any indication, the blonde was too.

He grabbed Shizuo's shoulders for support and let him take full control of their fucking, drilling right into him like his life depended on it.

He heard a deep growl and felt himself being filled with thick seed. The sensation sent him over the edge, his mouth opening in a silent cry as his whole body locked up, squeezing as much as he could out of Shizuo and into him, like some kind of reversal of the earlier blood-drinking.

They stood there against the wall for a few seconds, seeing stars, then gradually relaxed, breathing hard.

They both waited a bit, catching their breath after the intense workout, then silently redressed themselves.

Shizuo noticed that Izaya hadn't even bothered removing the cum filling him before putting his underwear and pants back on. A true pervert, through and through.

Though, well, he had been the one to fuck said pervert after draining him of his blood, so he wasn't that much better.

Shizuo wasn't too sure what to do next. Should he just leave and pretend none of this happened?

In the end, though, Izaya made that decision for him when he grabbed Shizuo's face for one last kiss.

"You know where to find me next time you're thirsty. See you around, Shizu-chan~" Izaya winked at him then left the alley with a casual wave of his hand, walking a bit funnily.

"Yeah." He said to the now empty alley. "See you around, flea."

**Author's Note:**

> Fun fact, I'd already started writing this before Shizaya Week, but the day 3 prompt was the perfect excuse to finish this.


End file.
